Optical lens

Patent metadata

Field	Value
Publication number	US-2020031990-A1
Application number	US-201716337077-A
Country	US
Kind code	A1
Filing date	Sep 27, 2017
Priority date	Sep 28, 2016
Publication date	Jan 30, 2020
Grant date	—

Abstract

An object is to provide an optical lens having low water-absorbing capacity and superior in heat resistance, transparency, and optical characteristics (refractive index, Abbe's number, and photoelastic coefficient). The optical lens includes a polyester resin containing a unit (A) of the following formula (1).

First claim

1 . An optical lens comprising a polyester resin comprising a unit (A) of the following formula (1):

wherein
R 1 is a hydrogen atom, CH 3 , or C 2 H 5 ,
R 2 and R 3 are each independently a hydrogen atom or CH 3 , and
n is 0 or 1.

2 . The optical lens according to claim 1 , wherein, in the formula (1), n is 1.

3 . The optical lens according to claim 1 , wherein, in the formula (1), R 1 , R 2 , and R 3 are hydrogen atoms.

4 . The optical lens according to claim 1 , wherein the polyester resin satisfies at least one of the following conditions (1) to (6):
(1) a glass transition temperature of the polyester resin is 120° C. or higher; (2) an amount of heat generated by the polyester resin at cooling crystallization is 5 J/g or less; (3) a water absorption percentage after immersion in water for 24 hours of the polyester resin is 0.25% or less; (4) an absolute value of photoelastic coefficient of the polyester resin is 40×10 −12 Pa −1 or less; (5) a refractive index (nd) for d-line wavelength light of the polyester resin is 1.60 or less; and (6) an Abbe's number (νd) of the polyester resin is 28 or more.

5 . The optical lens according to claim 1 , wherein the optical lens is an aspherical lens.

6 . The optical lens according to claim 1 , wherein the optical lens is for use in cameras.

7 . An optical system comprising a combination of the optical lens according to claim 1 and another optical lens.

Assignees

• Mitsubishi Gas Chemical Co

Inventors

• Yoshimura Yasuaki
• Honda Eiichi
• Noguchi Keita
• Satake Yuichiro

Classifications

• H04N23/55

  Optical parts specially adapted for electronic image sensors; Mounting thereof · CPC title

• G02B1/041 Primary

  Lenses · CPC title

• C08L2201/10

  Transparent films; Clear coatings; Transparent materials · CPC title

• G02B3/04

  with continuous faces that are rotationally symmetrical but deviate from a true sphere {, e.g. so called "aspheric" lenses} · CPC title

• C08G63/00 Primary

  Macromolecular compounds obtained by reactions forming a carboxylic ester link in the main chain of the macromolecule (polyester-amides C08G69/44; polyester-imides C08G73/16) · CPC title